A Saturday-night pull is the starting point for Stefan Golaszewski's new play, bleakly funny business when presented as forensically as this: a Lynx Africa-scented meeting in a nightclub pre-empting a pantomime grope by the fire exit, then a late-night journey home with only the interior fittings of an N73 bus to fuel conversation.

Russell Tovey and Jaime Winstone play Adam and Grace, our lacklustre couple. Adam tries hard to keep a flicker of eroticism in the night's tryst while Grace giggles and babbles, their progress towards the bedroom surviving a mini-drama over a lost Oyster card, a kebab, later an extended break for teeth brushing and a disagreement over sexy lighting. It starts to feel like an over-extended sketch about the ritual of one-night stands when the story suddenly broadens into something knottier, more sinister. Is that really a genial vacancy in Adam's manner or a deeper misanthropy? He has a long-term girlfriend, Ruth (Naomi Sheldon), and through flashback we hop around moments in their relationship – the early-date discovery that they both like Pizza Express olives launching a drab but genuine affection, all but vanished by the time they're sharing a flat and Ruth is cautiously plotting to wall-bracket their telly while Adam plans a Saturday night out on his own.

There's a glimpse of a living-room fight, verging on proper violence, that's shocking and horrible. It's the only time the underlying menace of this engaging play is allowed into plain view.